时间:2019-01-30 作者:英语课 分类:农业与发展


英语课

AGRICULTURE REPORT - Cover Crops
By Mario Ritter


Broadcast: Tuesday, March 23, 2004


This is Steve Ember with the VOA Special English Agriculture Report.


The idea to grow a crop that improves the land and prepares it for other crops is thousands of years old. But scientists continue to search for new and better ways to use what are called cover crops.


Aref Abdul-Baki is with the Agricultural Research Service of the United States Department of Agriculture. He works at the Sustainable Agricultural Systems Laboratory in Beltsville, Maryland.


Mister Abdul-Baki has found some cover crops that resist worms that attack tomatoes. These crops are sunn hemp 1, cowpea and velvet 2 bean. They are planted during the months when the main crops are not normally grown. In states with moderate climates like Maryland and Virginia, the winter months are a good time to grow cover crops.


For tomatoes, cover crops can be planted in September. They can be turned over in the soil in May. The same method can be used for other summer crops like peppers, sweet corn, green beans and some melons.


After the cover crop is cut and turned, the result is a layer of organic material. This will provide fertilizer for the new crop. Also, the cover crop provides extra nitrogen to the soil.


Cover crops mixed with soil into mulch prevents the growth of unwanted plants. It also keeps soil from drying out and prevents the loss of soil.


In hot, dry parts of California, cover crops help keep down soil temperatures. They also reduce water loss and erosion.


Mister Abdul-Baki has shown that cover crops can save farmers a lot of money. Tomato farmers, for example, have used methyl bromide to treat their soil before they plant their tomatoes. This chemical kills many kinds of organisms that harm crops. Such treatment can increase the size of the harvest. But the government restricts the use of methyl bromide. And countries have agreed to an international treaty to ban it.


Mister Abdul-Baki has found that farmers who use cover crops with tomatoes save one-thousand-four hundred dollars per hectare. Farmers save on chemicals and also fertilizer. And Mister Abdul-Baki says the farmer produce as many, or more, tomatoes per hectare as compared to no use of cover crops.


Some cover crops provide enough seed for the next growing season. This can reduce costs even more.


This VOA Special English Agriculture Report was written by Mario Ritter. This is Steve Ember.



n.大麻;纤维
  • The early Chinese built suspension bridges of hemp rope.古代的中国人建造过麻绳悬索桥。
  • The blanket was woven from hemp and embroidered with wool.毯子是由亚麻编织,羊毛镶边的。
n.丝绒,天鹅绒;adj.丝绒制的,柔软的
  • This material feels like velvet.这料子摸起来像丝绒。
  • The new settlers wore the finest silk and velvet clothing.新来的移民穿着最华丽的丝绸和天鹅绒衣服。
学英语单词
allergic reaction bronchiolitis
andels
aparecida
appassionato
Azikiwe, Nnamdi
be referred to as
beaver lamb
bellottis
bibliographic coupling
bidirectional communication link
birchler
blacked tape
brittle rock
buttered toast
calciturbidite
chaurs
color fastness to washing
Colpos
congenital dysplasia of the hip
conqueringly
delay unit
detail tape
diantipyrylmethane
diver-ticular hernia
double buffered in
drum-type vacuum filter
duodenoscopy
Eids
Elatostema macintyrei
electrically nonconducting material
ferrite-rod memory
fiiled incline blade type fan
file tools
firehalls
fish market
flower head
foetus papyraceus
fumaryl-alanine
galvanized square boat nail
gazzola
geothermal well
gin-fizz
give sb his walking ticket
harwig
hemorrhagic infarct of lung
herweg
hit-rates
iberoamerica
inverse micelle
kampelmen
lottery-winner
Lycophyta
mandibular foramen
mask pitch
Mastigina
maximum safety pressure
mergersort
minimum brightness
mousselines
mr.j.
nanohoneycombs
now, now
offences against public order
opprobrity
photoflash photography
pivot shots
private-language
program complexity
prolong life
purchasing budget
racial oppression and exploitation
rarae aves
rat out
receipted bill
recrystallization tcmperature
region base address
rubificative
sachemic
sales on consignment
schmaus
Semichi Pass
silvertungsten
sphenophyllum emarginatum brongn.
spiraling price
starting strip
staticizing
steam-vac metnod
steel mesh reinforcement
sucrosofate
symmetric bounded domain
theoretical reaction temperature
tin pipe
track sweeper
Trencin
undeveloped property
uniservo
unmann
virtual point
vsops
weight material
West Indies architecture
wordformat